Broadband constant-coefficient propagators

	Broadband constant-coefficient propagators
	Fu, LY
刊名	GEOPHYSICAL PROSPECTING
	2005-05-01
卷号	53 期号:3 页码:299-310
ISSN号	0016-8025
英文摘要	The phase error between the real phase shift and the Gazdag background phase shift, due to lateral velocity variations about a reference velocity, can be decomposed into axial and paraxial phase errors. The axial phase error depends only on velocity perturbations and hence can be completely removed by the split-step Fourier method. The paraxial phase error is a cross function of velocity perturbations and propagation angles. The cross function can be approximated with various differential operators by allowing the coefficients to vary with velocity perturbations and propagation angles. These variable-coefficient operators require finite-difference numerical implementation. Broadband constant-coefficient operators may provide an efficient alternative that approximates the cross function within the split-step framework and allows implementation using Fourier transforms alone. The resulting migration accuracy depends on the localization of the constant-coefficient operators. A simple broadband constant-coefficient operator has been designed and is tested with the SEG/EAEG salt model. Compared with the split-step Fourier method that applies to either weak-contrast media or at small propagation angles, this operator improves wavefield extrapolation for large to strong lateral heterogeneities, except within the weak-contrast region. Incorporating the split-step Fourier operator into a hybrid implementation can eliminate the poor performance of the broadband constant-coefficient operator in the weak-contrast region. This study may indicate a direction of improving the split-step Fourier method, with little loss of efficiency, while allowing it to remain faster than more precise methods such as the Fourier finite-difference method.
语种	英语
出版者	BLACKWELL PUBLISHING LTD
WOS记录号	WOS:000228396900001
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/64776]
专题	中国科学院地质与地球物理研究所
通讯作者	Fu, LY
作者单位	Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Fu, LY. Broadband constant-coefficient propagators[J]. GEOPHYSICAL PROSPECTING,2005,53(3):299-310.
APA	Fu, LY.(2005).Broadband constant-coefficient propagators.GEOPHYSICAL PROSPECTING,53(3),299-310.
MLA	Fu, LY."Broadband constant-coefficient propagators".GEOPHYSICAL PROSPECTING 53.3(2005):299-310.